21202120022001 has 4 divisors (see below), whose sum is σ = 28269493362672. Its totient is φ = 14134746681332.

The previous prime is 21202120021981. The next prime is 21202120022011. The reversal of 21202120022001 is 10022002120212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21202120022001 - 2²¹ = 21202117924849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21202120022011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3533686670331 + ... + 3533686670336.

It is an arithmetic number, because the mean of its divisors is an integer number (7067373340668).

Almost surely, 2^{21202120022001} is an apocalyptic number.

It is an amenable number.

21202120022001 is a deficient number, since it is larger than the sum of its proper divisors (7067373340671).

21202120022001 is an equidigital number, since it uses as much as digits as its factorization.

21202120022001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7067373340670.

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21202120022001 its reverse (10022002120212), we get a palindrome (31224122142213).

The spelling of 21202120022001 in words is "twenty-one trillion, two hundred two billion, one hundred twenty million, twenty-two thousand, one".